子视图UIImageView在Superview容器UIView中不会取水平中心

Question

我创建了一个自定义iOS弹出视图以显示图像视图。如果imageview的高度大于宽度，则不会在弹出窗口中居中。弹出窗口是背景透明的屏幕盖，白色弹出框以及容器中的标题标签+ UIImageView +按钮。由于某些原因，UIImageView不会在弹出容器视图中居中。我以编程方式100％完成此操作，如下所示。

我尝试将imageView.center设置为容器中心的点坐标，并设置superview.center和containerView.center。我已经尝试过CenterXAnchor，Leading和Trailing锚点以及其他一些东西。我应该能够将其居中放置在代码中，但不会在运行时居中！发生了什么事将其搁置一旁，但我无法弄清楚，我的高级同辈也无法解决。

class AlertView: UIView, AlertViewModel {
// MARK: - UI Element Definitions
// Containers
internal lazy var backgroundView: UIView = 
AlertViewUIElement.backgroundView()
internal lazy var containerView: UIView = 
AlertViewUIElement.containerView()
// Content
private lazy var titleLabel: UILabel = 
AlertViewUIElement.titleLabel()
private lazy var messageLabel: UILabel = 
AlertViewUIElement.messageLabel()
private lazy var imageView: UIImageView = 
AlertViewUIElement.imageView()
// Separator Elements
private lazy var separatorButtonTopLabel: UILabel = AlertViewUIElement.separatorLabel()
private lazy var separatorButtonMiddleLabel: UILabel = AlertViewUIElement.separatorLabel()
private lazy var bottomButtonSeparator: UILabel = AlertViewUIElement.separatorLabel()
// Buttons
private lazy var leftButton: UIButton = AlertViewUIElement.blueButton()
// Middle Button will be used for Three Button Popups
private lazy var middleButton: UIButton = AlertViewUIElement.blueButton()
// Right Button will be used for Single Button Popups
private lazy var rightButton: UIButton = AlertViewUIElement.redButton()

// Image Alert
convenience init(title: String, message: String? = nil, image: UIImage? = nil, leftButtonText: String? = nil, middleButtonText: String? = nil, rightButtonText: String = "Close", leftButton: (() -> ())? = nil, middleButton: (() -> ())? = nil, rightButton: (() -> ())? = nil) {
    self.init(frame: UIScreen.main.bounds)
    setupButtonActions(left: leftButton, middle: middleButton, right: rightButton)
    setupViewConstraints(title: title, message: message, image: image, leftButtonText: leftButtonText, middleButtonText: middleButtonText, rightButtonText: rightButtonText)
}


// MARK: - Alert View Constraints Setup

private func setupViewConstraints(title: String, message: String?, image: UIImage?, leftButtonText: String?, middleButtonText: String?, rightButtonText: String) {
    DispatchQueue.main.async {
        self.setupBackgroundView()
        self.setupContainerView()
        self.setupTitleLabel()
        self.titleLabel.text = title
        if let image = image {
            self.setupImageView(image: image)
        }
        self.setupSeperatorButtonTopLabel(showImage: image != nil)
        self.setupTwoButtons()
        self.leftButton.setTitle(leftButtonText, for: .normal)
        self.rightButton.setTitle(rightButtonText, for: .normal)
    }
}

// MARK: - Constraints

private func setupBackgroundView() {
    backgroundView.frame = frame
    addSubview(backgroundView)
    let tapGesture = UITapGestureRecognizer(target: self, action: #selector(dismissView))
    tapGesture.numberOfTapsRequired = 1
    backgroundView.addGestureRecognizer(tapGesture)
}

private func setupContainerView() {
    backgroundView.addSubview(containerView)
    let tapGesture = UITapGestureRecognizer(target: self, action: nil)
    tapGesture.numberOfTapsRequired = 1
    containerView.addGestureRecognizer(tapGesture)
    containerView.centerYAnchor.constraint(equalTo: backgroundView.centerYAnchor, constant: 0.0).isActive = true
    containerView.centerXAnchor.constraint(equalTo: backgroundView.centerXAnchor, constant: 0.0).isActive = true
    if UIDevice.isPad() {
        containerView.widthAnchor.constraint(equalToConstant: 450).isActive = true
    } else {
        containerView.widthAnchor.constraint(equalTo: self.widthAnchor, multiplier: 0.8).isActive = true
    }
}

private func setupTitleLabel() {
    containerView.addSubview(titleLabel)
    titleLabel.leadingAnchor.constraint(equalTo: containerView.leadingAnchor, constant: 8).isActive = true
    titleLabel.topAnchor.constraint(equalTo: containerView.topAnchor, constant: 0.0).isActive = true
    titleLabel.trailingAnchor.constraint(equalTo: containerView.trailingAnchor, constant: -8).isActive = true
    titleLabel.heightAnchor.constraint(equalToConstant: 48).isActive = true
}

private func setupMessageLabel() {
    containerView.addSubview(messageLabel)
    messageLabel.leadingAnchor.constraint(equalTo: containerView.leadingAnchor, constant: 8).isActive = true
    messageLabel.topAnchor.constraint(equalTo: titleLabel.bottomAnchor, constant: contentPadding).isActive = true
    messageLabel.trailingAnchor.constraint(equalTo: containerView.trailingAnchor, constant: -8).isActive = true
}
private func setupImageView(image: UIImage) {
    // TODO Center
    containerView.addSubview(imageView)
    self.imageView.image = self.resizeImage(image)
//        imageView.bindFrameToSuperviewBounds()

    imageView.topAnchor.constraint(equalTo: titleLabel.bottomAnchor, constant: contentPadding).isActive = true
    //        imageView.center.x = containerView.center.x
    //        imageView.centerXAnchor.constraint(equalTo: superview.centerXAnchor).isActive = true
    //        let trail = imageView.trailingAnchor.constraint(equalTo: containerView.trailingAnchor, constant: -8)
    //        let lead = imageView.leadingAnchor.constraint(equalTo: containerView.leadingAnchor, constant: 8)
    //        trail.priority = UILayoutPriority(rawValue: 999)
    //        lead.priority = UILayoutPriority(rawValue: 999)
    //        trail.isActive = true
    //        lead.isActive = true
}

private func setupSeperatorButtonTopLabel(showImage: Bool) {
    containerView.addSubview(separatorButtonTopLabel)
    separatorButtonTopLabel.leadingAnchor.constraint(equalTo: containerView.leadingAnchor).isActive = true
    if showImage {
        separatorButtonTopLabel.topAnchor.constraint(equalTo: imageView.bottomAnchor, constant: contentPadding).isActive = true
    } else {
        separatorButtonTopLabel.topAnchor.constraint(equalTo: messageLabel.bottomAnchor, constant: contentPadding).isActive = true
    }
    separatorButtonTopLabel.trailingAnchor.constraint(equalTo: containerView.trailingAnchor).isActive = true
    separatorButtonTopLabel.heightAnchor.constraint(equalToConstant: 1.0).isActive = true
}

// MARK: - Two Buttons

private func setupTwoButtons() {
    // Two horizontal buttons
    setupLeftButton()
    containerView.addSubview(separatorButtonMiddleLabel)
    separatorButtonMiddleLabel.leadingAnchor.constraint(equalTo: leftButton.trailingAnchor, constant: 0).isActive = true
    separatorButtonMiddleLabel.topAnchor.constraint(equalTo: separatorButtonTopLabel.bottomAnchor, constant: 0).isActive = true
    separatorButtonMiddleLabel.widthAnchor.constraint(equalToConstant: 1.0).isActive = true
    separatorButtonMiddleLabel.bottomAnchor.constraint(equalTo: containerView.bottomAnchor, constant: 0).isActive = true
    setupRightButton()
}

private func setupLeftButton() {
    containerView.addSubview(leftButton)
    leftButton.leadingAnchor.constraint(equalTo: containerView.leadingAnchor, constant: 0).isActive = true
    leftButton.topAnchor.constraint(equalTo: separatorButtonTopLabel.bottomAnchor, constant: 0).isActive = true
    leftButton.heightAnchor.constraint(equalToConstant: 40).isActive = true
    leftButton.bottomAnchor.constraint(equalTo: containerView.bottomAnchor, constant: 0).isActive = true
}

private func setupRightButton() {
    containerView.addSubview(rightButton)
    rightButton.leadingAnchor.constraint(equalTo: separatorButtonMiddleLabel.trailingAnchor, constant: 0).isActive = true
    rightButton.topAnchor.constraint(equalTo: leftButton.topAnchor, constant: 0.0).isActive = true
    rightButton.trailingAnchor.constraint(equalTo: containerView.trailingAnchor, constant: 0).isActive = true
    rightButton.heightAnchor.constraint(equalTo: leftButton.heightAnchor, constant: 0.0).isActive = true
    rightButton.widthAnchor.constraint(equalTo: leftButton.widthAnchor, constant: 0.0).isActive = true
}
}



extension AlertViewModel where Self: UIView {

// MARK: - Show and Hide the Alert View

func show(animated: Bool) {
    DispatchQueue.main.async {
        self.backgroundView.alpha = 0
        if var topController = UIApplication.shared.delegate?.window??.rootViewController {
            while let presentedViewController = topController.presentedViewController {
                topController = presentedViewController
            }
            let subviewsList = topController.view.subviews
            for view in subviewsList where view is AlertView {
                view.removeFromSuperview()
                break
            }
            topController.view.addSubview(self)
        }
        if animated {
            self.containerView.transform = CGAffineTransform(scaleX: 0.8, y: 0.8)
            UIView.animate(withDuration: 0.24,
                           animations: {
                            self.backgroundView.alpha = 1.0
                            self.containerView.transform = .identity
            },
                           completion: { _ in
                            self.backgroundView.alpha = 1.0
            })
        }
    }
}

func dismiss(animated: Bool) {
    DispatchQueue.main.async {
        if animated {
            self.backgroundView.alpha = 1.0
            self.containerView.transform = .identity
            UIView.animate(withDuration: 0.16,
                           animations: {
                            self.backgroundView.alpha = 0.0
                            self.containerView.transform = CGAffineTransform(scaleX: 0.8, y: 0.8)
            },
                           completion: { _ in
                            self.backgroundView.alpha = 0.0
                            self.removeFromSuperview()
            })
        } else {
            self.backgroundView.alpha = 0.0
            self.removeFromSuperview()
        }
    }
}

func resizeImage(_ image: UIImage) -> UIImage? {
    //        let newWidth = UIScreen.screenWidth * 0.6
    //        let newHeight = UIScreen.screenHeight * 0.2
    //        let scaledSize = CGSize(width: newWidth, height: newHeight)
    //        return image.imageWithSize(scaledSize)
    let maxSize = CGSize(width: 295, height: 300)
    let imageSize = image.size
    var ratio: CGFloat = 0

    if imageSize.width > imageSize.height {
        ratio = maxSize.width / imageSize.width
    } else {
        ratio = maxSize.height / imageSize.height
    }

    let scaledSize = CGSize(width: imageSize.width * ratio, height: imageSize.height * ratio)
    var resizedImage = image.imageWithSize(scaledSize)

    if imageSize.height > imageSize.width {
        let left = (maxSize.width - (resizedImage?.size.width ?? 0)) / 2
        resizedImage = resizedImage?.withAlignmentRectInsets(UIEdgeInsets(top: 0, left: -left, bottom: 0, right: 0))
    }
    return resizedImage
}
}

可以使用init调用此弹出窗口，传递图像，并且该图像应位于容器框/弹出窗口的中心。有什么事我看不到还是做错了吗？谢谢